Field of the Invention
The present invention relates to a detecting apparatus irradiating light toward a detection material and detecting reflected light from the detection material, and an image forming apparatus.
Description of the Related Art
In recent years, there is a growing need for higher image quality and better ecological measures in image forming apparatuses such as copiers, laser beam printers, and inkjet printers.
In situations where high image quality is required, conventionally, a patch image of a reference pattern formed on a recording material (a detection material) is detected by a detecting apparatus arranged inside an image forming apparatus. In addition, output data of the detecting apparatus is compared with data of the reference pattern to create correction data to be used for correcting image quality such as a tinge of an image to be formed next.
On the other hand, as an ecological measure, a detecting apparatus detects an image representing surface properties of a recording material (a recording medium), and by determining a type of the recording material, image formation conditions are changed in accordance with the type of the recording material so that printing is performed with the least amount of energy.
Since the detecting apparatus used in these techniques read a patch image on a recording material or an image representing surface properties of the recording material, the detecting apparatus is desirably arranged inside a transport path along which the recording material is transported during image formation.
However, arranging the detecting apparatus inside a transport path creates a risk of the detecting apparatus being contaminated by paper powder or the like and losing the ability to accurately detect a patch image on a recording material surface properties of the recording material.
As a solution to such a problem, a configuration is known in which a shutter (an opening/closing member) that opens and closes an opening of a detecting apparatus is disposed (refer to Japanese Patent Application Laid-open No. 2013-205258). An imaging portion is provided with an illuminating light source (a light emitting element) which emits light toward a reference chart (a detection material) through an opening and a sensor (a light receiving element) which receives reflected light from the reference chart. By opening the shutter (the opening/closing member) during imaging and closing the shutter during normal transportation of a recording material during which imaging is not performed, contamination by paper powder and the like is minimized.
In addition, in order to improve reading accuracy by the detecting apparatus, a distance between the light receiving element and the recording material is desirably controlled to be constant. Since a constant distance can be realized by bringing the detecting apparatus into close contact with the recording material during detection, a method is conceivable in which the detecting apparatus is abutted against an opposing surface that oppose the detecting apparatus in the transport path to sandwich the recording material.
However, constantly abutting the detecting apparatus against the opposing surface of the transport path raises concerns that a defective image may be created due to friction or the like and that a paper jam or the like of recording material with low stiffness may occur. Therefore, the detecting apparatus is desirably brought into contact with the opposing surface of the transport path during reading and separated from the opposing surface when reading is not performed.
As a technique for realizing such a contacting/separating operation of a detecting apparatus, for example, Japanese Patent Application Laid-open No. 2013-148503 proposes a configuration in which a colorimetric unit (an apparatus main body of a detecting apparatus) provided with a colorimetric sensor (a light receiving element) moves between a first position where the colorimetric unit presses a recording material (a detection material) and a second position where the pressing is released.